Embedded DNS

• US 20070255848A1
• Filed: 02/12/2007
• Published: 11/01/2007
• Est. Priority Date: 09/08/2004
• Status: Active Grant

• Current Assignee: CradlePoint Incorporated (Telefonaktiebolaget LM Ericsson)
• Original Assignee: CradlePoint Incorporated (Telefonaktiebolaget LM Ericsson)
• Inventors: Johnson, Dave, Sewall, Pat
• Granted Patent: US 7,962,569 B2
• Time in Patent Office: Days
• US Class Current: 709/232
• CPC Class Codes: H04L 61/4511 using domain name system [DNS]
• CPC Class Codes: H04L 69/40 for recovering from a failure of a protocol instance or entity, e.g. service redundancy protocols, protocol state redundancy or protocol service redirection management of faults, events, alarms or notifications in data switching networks H04L41/06

Abstract

An embodiment is directed to a method for selectively routing a DNS request in which a DNS request to translate a domain name is received from a local client device. The DNS request is directed to a remote DNS server on a remote network. A link status to the remote network is identified. If the link status indicates that a connection to the remote network is not possible, the DNS request is routed to a locally embedded DNS server. If the link status indicates that a connection to the remote network is possible, the DNS request is routed to the remote DNS server on the remote network.

Claims

1. A method for selectively routing a DNS request, comprising:

receiving a DNS request to translate a domain name, the DNS request being received from a local client device and directed to a remote DNS server on a remote network;

identifying a link status to the remote network; and

if the link status indicates that a connection to the remote network is not possible, routing the DNS request to a locally embedded DNS server.

2. The method of claim 1, further comprising, if the link status indicates that a connection to the remote network is possible, routing the DNS request to the remote DNS server on the remote network

3. The method of claim 1, further comprising after routing the DNS request to the locally embedded DNS server, determining if the domain name can be translated locally by the embedded DNS server, returning the translated address to the client device if the domain name can be translated locally, and returning an alternate address to the client device if the domain name cannot be translated locally.

4. The method of claim 3, wherein returning an alternate address comprises returning a local address of a device containing the locally embedded DNS server.

5. The method of claim 1, further comprising, if the DNS request is routed to the remote DNS server, updating a DNS database utilized by the locally embedded DNS server.

6. The method of claim 5, wherein updating comprises updating the DNS database based on an evaluation of the domain name in the DNS request, a translated address returned from the remote DNS server, and previously monitored network request activity received from the client device.

7. The method of claim 6, wherein updating comprises updating the DNS database to include information reflective of domain name and the translated address, the updated information being for use by the locally embedded DNS server in translating a DNS request for the domain name.

8. The method of claim 1, further comprising:

receiving a request for content, the request for content being a request received from the local client device and directed to a translated address on the remote network returned in response to the DNS request; and

if the link status indicates that a connection to the remote network is not possible, returning link fault content to the local client device

9. The method of claim 8, wherein identifying a link status to the remote network comprises determining the existence of a device link fault or a remote link fault.

10. The method of claim 9, wherein returning link fault content comprises returning device link fault content upon determining a device link fault and returning remote link fault content upon determining the existence of a remote link fault.

11. A computer readable medium having computer executable instructions for:

receiving a DNS request to translate a domain name, the DNS request being received from a local client device and directed to a remote DNS server on a remote network;

identifying a link status to the remote network; and

if the link status indicates that a connection to the remote network is not possible, routing the DNS request to a locally embedded DNS server.

12. The medium of claim 11, having further instructions for routing the DNS request to the remote DNS server on the remote network if the link status indicates that a connection to the remote network is possible.

13. The medium of claim 11, having further instructions for determining if the domain name can be translated locally by the embedded DNS server, returning the translated address to the client device if the domain name can be translated locally, and returning an alternate address to the client device if the domain name cannot be translated locally.

14. The medium of claim 13, wherein the instructions for returning an alternate address include instructions for returning a local address of a device containing the locally embedded DNS server.

15. The medium of claim 11, having further instructions for updating a DNS database utilized by the locally embedded DNS server.

16. The medium of claim 15, wherein the instructions for updating include instructions for updating the DNS database based on an evaluation of the domain name in the DNS request, a translated address returned from the remote DNS server, and previously monitored network request activity received from the client device.

17. The medium of claim 16, wherein the instructions for updating include instructions for updating the DNS database to include information reflective of domain name and the translated address, the updated information being for use by the locally embedded DNS server in translating a DNS request for the domain name.

18. The medium of claim 11, further comprising:

receiving a request for content, the request for content being a request received from the local client device and directed to a translated address on the remote network returned in response to the DNS request; and

if the link status indicates that a connection to the remote network is not possible, returning link fault content to the local client device.

19. The medium of claim 18, wherein the instructions for identifying a link status to the remote network include instructions for determining the existence of a device link fault or a remote link fault.

20. The medium of claim 19, wherein the instructions for returning link fault content include instructions for returning device link fault content upon determining a device link fault and returning remote link fault content upon determining the existence of a remote link fault.

21. A system for selectively routing a DNS request, comprising:

a locally embedded DNS server;

a router operable to receive a DNS request to translate a domain name, the DNS request being received from a local client device and directed to a remote DNS server on a remote network; and

a link monitor operable to identify a link status between the system and the remote network;

wherein router is operable to route the DNS request to a locally embedded DNS server if the link status indicates that a connection to the remote network is not possible.

22. The system of claim 21, wherein the locally embedded DNS server is operable to rout the DNS request to the remote DNS server on the remote network if the link status indicates that a connection to the remote network is possible.

23. The system of claim 21, wherein the locally embedded DNS server is operable to determine if the domain name can be translated locally, to return the translated address to the client device if the domain name can be translated locally, and to return an alternate address to the client device if the domain name cannot be translated locally.

24. The system of claim 23, wherein the locally embedded DNS server is operable to return the alternate address in the form of a local address of a device containing the locally embedded DNS server.

25. The system of claim 21, wherein the locally embedded DNS server is operable to translate domain names identified in a DNS database, the system further comprising an activity monitor operable to update the DNS database.

26. The system of claim 25, wherein the activity monitor is operable to update the DNS database based on an evaluation of the domain name in the DNS request, a translated address returned from the remote DNS server, and previously monitored network request activity received from the client device.

27. The system of claim 26, wherein the activity monitor is operable to update the DNS database to include information reflective of the domain name received in a DNS request and a translated address returned from the remote DNS server.

28. The system of claim 21, wherein the router is operable to:

receive a request for content, the request for content being a request received from the local client device and directed to a translated address on the remote network returned in response to a DNS request;

if the link status indicates that a connection to the remote network is not possible, cause link fault content to be returned to the local client device; and

if the link status indicates that a connection to the remote network is possible, route the request for content to the translated address.

29. The system of claim 28, wherein the fault monitor is operable to identify a link status by determining the existence of a device link fault or a remote link fault.

30. The system of claim 29, wherein the link fault content includes device link fault content when the link status indicates a device link fault, and the link fault content includes remote link fault content when the link status indicates the existence of a remote link fault.